The present invention relates generally to a bearing assembly for use in an x-ray tube and more particularly to a multiple row bearing assembly for use in an x-ray tube.
Inner rotation x-ray tube bearings for use in a rotating anode x-ray tube device are well known in the prior art. One typical type of x-ray tube support bearing includes ball bearing positioned between an inner and outer race to provide bearing support for the assembly. Although such bearing designs are common, they are not without disadvantages.
It is possible for present bearing designs to transfer torque through the ball bearings to the outer race. This transfer of torque can result in the rotation of the outer race which may in turn contribute to chatter of the bearing assembly. This is highly undesirable. In addition, present designs with a stationary, or nearly stationary, outer race may result in high velocities of the ball bearings during operation. The combination of rubbing due to race rotation, chatter, and high ball velocities can result in high acoustic noise generation during operation. This is, of course, highly undesirable.
Considerable effort and time has gone into the advancement of systems to lubricate the ball bearings in such designs in an effort to reduce these negative characteristics. These advancements in lubrication, however, can come at the expense of an increase in cost of the bearing assembly. In addition, such lubrication systems often leave room for improvement in the reduction of ball speed, torque transfer, and chatter. Reductions in such characteristics are highly desirable as they may lead to reduced wear on the ball bearings, an increase in the life cycle of the bearings, a reduction in acoustic noise generation, and possibly an increased anode run speed of the tube.
Therefore, there is a need for an x-ray tube bearing assembly that reduces ball speed, reduces transfer torque, reduces chatter, reduces acoustic noise generation, and may allow for an increase in the anode run speed of the tube.
It is, therefore, an object of the present invention to provide a bearing assembly for use in an x-ray tube with reduced ball speed, transfer torque, chatter, and acoustic noise generation. It is a further object of the present invention to provide a bearing assembly for an x-ray tube that may allow for increased anode run speeds.
In accordance with the objects of this invention, a multiple row x-ray tube bearing assembly is provided. The multiple row x-ray tube bearing assembly includes an inner bearing member and an outer bearing member. The outer bearing member surrounds the inner bearing member and both bearing members rotate about the same primary axis. A free rotational intermediate race element positioned between the inner bearing member and the outer bearing member allows both the inner bearing member and the outer bearing member to rotate independently of each other. The ability of each bearing member to rotate independently can reduce ball velocity, outer race rotation, rubbing, and chatter, among other benefits.
Other objects and features of the present invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and the appended claims.